Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Why Sunnyvale Homeowners Choose ES Windows Construction
Rowan Construction Group Es Windows in Sunnyvale provides independent construction service across the city, from Lakewood Village teardown-rebuilds to ADU additions off El Camino Real. We install, reframe, and finish ES Windows units as an independent trade partner, not an authorized dealer, which means we handle the rough opening, flashing integration, and finish carpentry the manufacturer’s installation instructions specify without making warranty claims on their behalf. If you’re pricing ES Windows work in Sunnyvale, call (650) 405-3637 and we’ll deliver a written line-item estimate before any work starts.
ES Windows has a strong presence in Sunnyvale because the Series 3000 slider and ES-6000 single-hung hit the price point that makes sense for the city’s teardown-rebuild cycle and ADU boom. Contractors here aren’t installing one window at a time; they’re ordering twenty units for a ground-up custom build or six units for a backyard cottage. That volume means local crews know these products well, and it means we see the same failure patterns repeat across enough homes to know which repairs hold and which don’t.
Why Trust Rowan Construction Group Sunnyvale for Your ES Windows Construction?
We’ve installed and serviced ES Windows products across hundreds of Sunnyvale homes since 2007. Grant Rowan, our owner, grew up in Beverly Hills and picked up his first framing hammer before he could drive, trailing a family friend who remodeled homes in the flats off Wilshire. He trained in construction technology at Santa Monica College, where coursework covered structural load calculations, blueprint reading, and site safety - fundamentals he still references when scoping a job today. For more than two decades Grant and his crew have worked across Sunnyvale, including extensive remodel and build-out work in the Lakewood Village neighborhood near Washington Park, handling everything from permitted additions to full gut renovations. He’s known for delivering written line-item estimates before any contract is signed - material costs, labor hours, and subcontractor scope listed separately so the client knows exactly where each dollar goes.
Our ES Windows work is specific. We stock OEM-matched vinyl balances, weatherstrip, and sill hardware for the ES-6000 and Series 3000 lines, and we measure for aftermarket IGUs when the original dual-pane seal has failed but the frame and sash profile are still sound. We know the difference between a repairable balance issue and a racked frame that will keep leaking air no matter how many parts you throw at it. Under Clause 1 of the Haven Standard, the price is written before anyone starts; under Clause 3, no change proceeds without a signed change order. That’s the discipline that has kept our projects within a few percent of the agreed cost across 4,000-plus jobs.
Every crew member is background-checked and uniformed; a live person answers our calls 24/7; and every visit includes a documented photo record as standard, not an upgrade. When we leave a Sunnyvale jobsite, the customer has evidence of what we found and what we did.
Common ES Windows Construction Problems We Fix in Sunnyvale

- Fogged or failed dual-pane IGU seals in Series 3000 sliding glass doors. The west- and south-facing openings common in Sunnyvale’s 1950s-1970s ranch stock take heavy afternoon sun across the Bay, and the thermal cycling eventually separates the IGU seal. You see condensation between the panes that won’t wipe off. We measure the existing glass and source a replacement insulated unit rather than replacing the entire door if the roller track and frame are still square.
- Sticking or dragging sashes on the ES-6000 single-hung. Worn vinyl balances are the usual culprit, but in Sunnyvale we also find swollen wood shims behind the jamb after wet winters - the Bay clay soils hold moisture, and older homes without proper sill pan drainage wick it into the framing. We pull the sash, replace both balances with OEM-matched parts, and reset the shims with composite material that won’t swell. “Measure it twice, write it down, then build it” - that’s how we avoid the callback.
- Water infiltration at the sill and head flashing on Series 8000 aluminum-clad casements. Failed caulk joints and mis-pitched sill pans let water run behind the cladding instead of out the weep holes. In Sunnyvale’s older homes with original rough openings, the framing isn’t always plumb, and a casement installed without proper shim and flash integration will leak during the first winter storm. We remove the unit, reflash with new butyl tape and a kick-out diverter, and reset it to the manufacturer’s pitch specification.
- Weep-hole blockage and cracked vinyl weep covers in ES-2000 picture windows. These fixed units don’t open, so owners rarely notice the weep system has failed until the sill plate shows discoloration. Pooling condensation against the sill plate is common in Sunnyvale homes with irrigation systems that overspray the exterior wall. We clear the weep channels, replace cracked covers, and assess whether the surrounding framing has taken enough moisture to require repair.
- Racked frames from foundation movement in post-tensioned slab homes. Sunnyvale’s significant subset of late-1970s through 1980s homes sits on post-tensioned concrete slabs, and the expansive Bay clay beneath shifts with the seasons. A window frame that was square at install can twist enough that the sash won’t seat properly no matter how many new balances you install. We tell owners honestly when the frame is past saving and replacement is the only fix that won’t leak air and water.
Before
AfterES Windows Parts & Our Repair-vs-Replace Approach
We source OEM ES Windows balances, weatherstrip, and sill hardware when the unit is repairable. For IGUs on units past fifteen years or so, we use measured aftermarket glass from our local supplier - the performance spec matches, and the lead time is shorter than factory ordering. If the frame is racked from foundation movement or the sash profile is cracked at the weld, we tell Sunnyvale owners to replace the unit. Chasing seal and balance repairs on a compromised frame wastes money and still leaves you with a window that leaks.
Our stock for Sunnyvale includes common ES-6000 balance sets, Series 3000 roller assemblies, and standard weatherstrip profiles. Most repairs that don’t require glass replacement finish in one visit. For IGU swaps or full unit replacements, we measure on the first visit and schedule install once the glass or unit arrives. Call (650) 405-3637 to schedule your free estimate - we’ll tell you which category your window falls into.
Our ES Windows Service Process - Step by Step

- 1
Diagnosis with documentation. We inspect the unit, identify the series and approximate age, and test operation, balance tension, and seal integrity. We photograph the condition and any water damage to the surrounding framing. You get the photo record before we leave.
- 2
Written scope and price. Under Clause 1 of the Haven Standard, we deliver a flat written price with material costs, labor hours, and any subcontractor scope listed separately. No work starts until you have the number in writing.
- 3
Repair or install with OEM-compatible parts. We use OEM-matched components for ES Windows units when available, measured aftermarket glass for older IGUs, and new construction-grade flashing and sealant for full replacements. Every step follows the manufacturer’s installation instructions for rough opening prep, sill pan integration, and shimming.
- 4
Operational test and final documentation. We cycle the sash or door ten times, check lock engagement, and verify weep drainage with a water test. The photo record from arrival is supplemented with completion photos showing the finished work.
- 5
Warranty registration and follow-up. Our 365-Day Done Right Promise covers the installation workmanship. We explain what the manufacturer’s warranty covers on parts and what our promise covers on labor, in writing, before we leave.
ES Windows Products We Service & Install in Sunnyvale
We work with the full ES Windows residential line: Series 3000 vinyl sliding glass doors for patio and ADU openings; ES-6000 vinyl single-hung windows for standard wall construction; Series 8000 aluminum-clad casements for ventilation and egress requirements; and ES-2000 vinyl picture and fixed windows for non-operating openings. For Sunnyvale’s teardown-rebuild market, we also handle impact-rated specifications from ES Windows where the architect or engineer calls for them, particularly on homes with large west-facing glass areas. We stock balances, rollers, weatherstrip, and hardware for the 3000 and 6000 series locally; glass and full units ship from our regional supplier with typical lead times of two to three weeks.
We Also Service These Brands

Rowan Construction Group Sunnyvale sources across fifty-plus vetted brands. For projects that extend beyond ES Windows, we install KraftMaid and Wellborn cabinets, Cambria and Silestone countertops, and Kohler and Toto fixtures - or explore our Kitchen Remodeling services for full-room renovations. Our written quotes pull from this sourcing depth so the numbers are honest, not padded with single-source markup.
FAQs - ES Windows Construction Service in Sunnyvale
No. We are an independent ES Windows service provider, not an authorized dealer or warranty agent. We install, repair, and finish ES Windows products according to the manufacturer’s published instructions, but we do not represent ES Windows or process warranty claims on their behalf. Our 365-Day Done Right Promise covers our workmanship; manufacturer’s defects are between the owner and ES Windows.
We use OEM-matched parts - balances, rollers, weatherstrip, and hardware - sourced from ES Windows distributors when available. For IGUs on older units, we use measured aftermarket glass that matches the thermal performance spec. We tell you which category your repair falls into before any work starts, in writing.
Most balance, roller, and weatherstrip repairs finish in two to four hours. IGU replacements require measurement, then a second visit for glass installation once the unit is fabricated - typically one to two weeks total. Full window or door replacements depend on lead time, usually two to three weeks from order to install. We give you the timeline in writing with the price.
We service and install Series 3000 vinyl sliding glass doors, ES-6000 vinyl single-hung windows, Series 8000 aluminum-clad casements, and ES-2000 vinyl picture and fixed windows. If your unit is an older or discontinued ES Windows line, we assess whether repair parts are still available and advise honestly.
Manufacturer warranties typically cover defects in materials and workmanship from the factory, not field damage or improper installation. Having an independent contractor service your window does not automatically void a valid manufacturer’s warranty, but damage caused during service - by any contractor - is not covered. We document our work with photos to protect both parties. If your unit is still under factory warranty, we note that in our scope and recommend you contact ES Windows directly for defect-related issues.
Yes. Our 365-Day Done Right Promise covers installation workmanship for one full year. If it’s not done right, we make it right - backed by The Haven Standard, not a handshake. The manufacturer’s warranty covers their parts; our promise covers our labor, flashing integration, and finish work.
ES Windows service in Sunnyvale ranges from roughly $300-$800 for balance and hardware repairs to $4,500-$15,000 for full window replacement and $8,000-$25,000 for impact window installation on larger openings. Home additions with multiple ES Windows units typically fall within the $45,000-$130,000 range depending on scope. Every quote is flat, written, and itemized before work starts. Call (650) 405-3637 for an exact quote - estimates are free.
| Service | Price Range in Sunnyvale |
|---|---|
| Window Replacement | $4,500 - $15,000 |
| Impact Window Installation | $8,000 - $25,000 |
| Roof Repair | $400 - $1,800 |
| Home Addition | $45,000 - $130,000 |
Book Your ES Windows Service in Sunnyvale, CA

Call (650) 405-3637 to schedule your free estimate. We’ll inspect your ES Windows units, photograph the condition, and deliver a written line-item price before any work starts. Under the Haven Standard, the number you agree to is the number you pay - no change proceeds without a signed change order, and every project finishes within a few percent of that written price.
Written by Grant Rowan, Owner at Rowan Construction Group Sunnyvale, serving Sunnyvale since 2007.







Before
After
Before
After
Before
After